Lol, dude I'm a huge fan of yours. the shit you come up with is genius. Not to sound like a little kid but, seriously your my fucking hero! aalso are those some kind of grunge brush?
Thanks a lot! ! Also, nope no grunge brushes. I try to never use brushes, feels like cheating to me XD (unless I make the brushes). The texture you see is actually a photo of scratched metal. Desaturate, increase contrast, adjust levels (get it as close to a pure black and white as possible, less shades of grey) and then adjust the blending mode, I believe this was multiply.